Composite Resin Cement Research Articles

Utilization of Er:YAG Laser in Retrieving and Reusing of Lithium Disilicate and Zirconia Monolithic Crowns in Natural Teeth: An In Vitro Study

The study examined the effect of noninvasive crown retrieval/reuse process using an erbium-doped yttrium aluminum garnet laser (Er:YAG). Twenty-six extracted human teeth were prepared for a crown. The crown was milled using lithium disilicate (LD) and zirconia (Z) materials, n = 13 per group, with three for scanning electron microscopy (SEM). The crown was luted using composite resin cement and subjected to a laser retrieval process. After the retrieval process, the crown was cleaned, re-cemented and laser-retrieved two more times, without and with additional tooth reduction mimicking clinical refreshment of dentin. Retrieval time and temperature were analyzed using analysis of variance (ANOVA). Surface changes were observed through SEM. The retrieval times were 267.1 ± 130.43, 220 ± 79.09, 277.1 ± 126.44, 368.4 ± 136.14, 355 ± 159.39, and 419.2 ± 121.36 s for first, second, third LD and Z groups, respectively (p = 0.009). The maximal temperatures were 23.95.1 ± 1.89 °C, 24.86 ± 2.01 °C, 24.17 ± 1.53 °C, 22.88 ± 1.51 °C, 24.03 ± 1.74 °C, and 21.99 ± 1.32 °C for first, second, third LD and Z groups, respectively (p = 0.006). Er:YAG laser crown removal is an effective retrieval tool for all-ceramic crowns. Minimal changes to teeth and crowns were observed following laser irradiation.

Measuring the polymerization stress of self-adhesive resin composite cements by crack propagation

ObjectivesTo test the polymerization stress of nine self-adhesive resin composite cements (G-CEM, iCEM, Bifix SE, Maxcem Elite, PANAVIA SA, SoloCem, SmartCem 2, SpeedCEM, RelyX Unicem 2) and one glass ionomer cement (control group; Ketac Cem).Materials and methodsThe crack propagation of a feldspar ceramic (n = 130) was determined by measuring crack lengths that originated from Vickers indentations, prior to and after the application and polymerization of the self-adhesive resin cements. Results for crack propagation were converted to polymerization stress values, and statistical analysis was performed using one-way ANOVA followed by Scheffé post hoc test.ResultsSmartCem 2 presented higher stress values than iCEM, SoloCem, and Ketac Cem, while Ketac Cem showed lower values than Bifix SE, Maxcem Elite, SmartCem 2, SpeedCEM, and RelyX Unicem 2.ConclusionsSelf-adhesive resin composite cements differ in their polymerization stress, which may affect the durability of the restoration. For restorations made from ceramics with lower flexural strength, such as feldspar ceramics, resin composite cement materials with less polymerization stress should be preferred.Clinical RelevanceAs a high polymerization shrinkage may increase crack propagation, the determination of the polymerization stress of self-adhesive resin composite cements employed for fixing all-ceramic restorations is an important factor.

Forensic study of mechanical properties of dental fillings after immersion in marine environment

Human identification and postmortem intervals can be difficult to estimate when corpses are found in drowning situations, and forensic odontologists can bring valuable input to forensic science investigations of this type. Studies that simulate real scenarios are crucial for providing parameters that can be used in real cases. The present study created the necessary circumstances, i.e. immersion in a marine environment, to estimate the changes in the mechanical properties (Knoop microhardness, roughness, and color) of various dental fillings (silver amalgam, composite resin, and glass ionomer cement) over different immersion periods of time (one and three months). The silver amalgam fillings showed a significant increase in surface roughness. The composite resin fillings showed statistically significant increases in surface roughness and Knoop microhardness, and the glass ionomer cement showed a significant increase in surface roughness. These results lead to the conclusion that teeth restored with silver amalgam, composite resin, and glass ionomer cement, when subjected to immersion in marine environments, produce different changes in surface roughness, Knoop microhardness, and color properties depending on the length of immersion time. These findings could help in the field of forensic science to accurately estimate immersion time of dead bodies found in marine environments.

Phosphate dental cements aged in vivo up to 25 years

ABSTRACT Phosphates particularly zinc phosphates is a family of conventional dental cements that was developed a century ago and has been in use until today despite the fact that a number of new resin composite cements have been introduced in the market through the years. A close inspection of the in vivo aged samples provides insides to the margins and to the micro-leakage thus would sharpen the understanding and inspire the future development of the cements and cementation interfaces between the dental restorations and the natural tooth or implant abutment. This study highlights the cementation interface and its structural change during in vivo aging. Besides the focused studies on phosphate cements, limited investigation has also been performed on resin composite cements as references.

Bond strength and computational analysis for silane coupling treatments on the adhesion of resin block for CAD/CAM crowns.

The purposes of this study were to evaluate the shear bond strength and perform the computational analysis for silane coupling treatments on the adhesion between CAD/CAM composite resin and resin cement. As silane coupling agents, γ-methacryloyloxy propyltrimethoxysilane, 8-methacryloyloxyoctyl trimethoxysilane, and 3-methacryloyloxypropyl trichlorosilane were used. The shear bond strengths were influenced by the silane coupling agent used, its application method, and acid addition. There was no correlation between the contact angle and shear bond strengths. The steric energy difference between a silane coupling agent and its corresponding hydrolyzed trisilanol compound, ∆E, was calculated by the molecular mechanics method. There was a moderate or strong linear correlation between ∆E and shear bond strengths in treatment without acid addition and a weak correlation between them in treatment with acid addition. Computational analysis could suggest the different path of silane coupling treatments of CAD/CAM composite resin in the presence or absence of acid.

Commercially Available Fluoride-Releasing Restorative Materials: A Review and a Proposal for Classification.

Resin composite and glass ionomer cement (GIC) are the most commonly used dental materials to perform direct restorations. Both have specific characteristics that explain their popularity and their limits. More than 20 years ago, the first attempt (followed by others) to combine the advantages of these two families was performed with compomers, but it was not very successful. Recently, new formulations (also called ‘smart materials’) with claimed ion release properties have been proposed under different family names, but there are few studies on them and explanations of their chemistries. This comprehensive review aims to gather the compositions; the setting reactions; the mechanical, self-adhesive, and potential bulk-fill properties; and the ion release abilities of the large existing families of fluoride-releasing restorative materials and the new restorative materials to precisely describe their characteristics, their eventual bioactivities, and classify them for an improved understanding of these materials. Based on this work, the whole GIC family, including resin-modified and highly viscous formulations, was found to be bioactive. Cention N (Ivoclar Vivadent, AG, Schaan, Lietschentein) is the first commercially available bioactive resin composite.

Comparison of In Vitro Dose Perturbation Effects of Amalgam, Composite Resin, Glass Ionomer Cement and Ketac Silver During Head and Neck Radiation with Photon Beam

The most common oral manifestation from head and neck radiotherapy is mucositis. A part of complications is backscattering from metallic dental materials in radiation field, resulting in a dosage enhancement at the tissue-metal interface. The proper management of the patient’s restorative materials must be performed preoperatively to reduce these complications. This research compared the relative dose enhancement (RDE) in the different restorative materials (Amalgam, Composite resin, Glass ionomer cement and Ketac Silver®), the different tooth preparations (Class I, Class I other, Class II MOD, Cusp Tipping and Core build-up) and the location of ionizing chamber (buccal, occlusal, lingual surface). The dimension of controlled 20 teeth are as followed lower third molar, buccolingual width (10.41±0.82mm), mesiodistal width (11.28±0.72mm), dentin and enamel buccolingual width (1.5±0.5mm). The experiment is set using a modular radiation beam analyzer with at least 2 cm water as soft tissue equivalent material, 3 times irradiated with LINAC 6MV 200MU. The backscattering occurred in the amalgam filled tooth at the buccal and occlusal aspect in every preparation. The highest RDE occurring at the buccal aspect of cusp tipping amalgam filled tooth was 2.7%. In the lingual aspect, every preparation of amalgam filled tooth demonstrated lower RDE. The composite resin and glass ionomer cement produced low backscattering, while Ketac Silver® produced higher RDE. For any amalgam restorations in the radiation field, we recommended using the one-layer glass ionomer technique, which is suitable in preparing patient ahead of head and neck radiation. The recommended filling technique may decrease mucositis the adjacent area and improve the patient’s quality of life.

Effect of Tack Cure on Polymerization Shrinkage of Resin-based Luting Cements.

Self-cure after tack cure could result in a lower polymerization shrinkage in some resin-based luting cements, which is closely related to lower degree of cure.

Evaluation of Water Sorption and Solubility of Different Dental Cements at Different Time Interval

Background: The clinical durability of dental cements is determined by dimensional stability. Water sorption and solubility of dental cements in distilled water have not been tested sufficiently. Aims: To evaluate and compare the water sorption and solubility of four different dental cements for permanent cementation at different time interval. Materials and Methods: Four different dental cements were selected: 1. Resin modified glass ionomer cement (Rely X luting2), 2. Poly acid modified composite resin cement (PermaCem Compomer), 3. Self-etching, self-adhesive dual cure composite resin cement (BeautiCem SA) and 4. Self-adhesive, dual cure composite resin cement (PermaCem 2.0). 120 discs were prepared, 30 discs for each group using Teflon molds (15±0.1mm in diameter and 1±0.1 mm in thickness). The discs were dried in a desiccator at 37co and weighted daily until a stable weight (M1) was achieved using an electronic digital balance with accuracy of 0.0001g. The discs were immersed in distilled water for different time intervals (1, 7, 14, 21, 28 and 35 days) and the weight (M2) was recorded. The discs were replaced in a desiccator and weighed daily until stable weight (M3) was achieved. Water sorption and solubility in µg/mm³ were calculated using the following equations: Wsp=(M2-M3)/V; Wsl=(M1-M3)/V. Data analyzed using ANOVA and Tukey’s Post hoc test. Results: The results showed that there was a significant difference between the different dental cements and time intervals for both water sorption and solubility. RelyX luting2 exhibited the highest water sorption and solubility values at different time interval, whereas Permacem 2.0 showed the lowest values (P≤0.05). Conclusion: Four types of dental cements of different compositions showed different behavior on water sorption and solubility. Resin cements are recommended for the permanent cementation of indirect restorations. Dental cements exhibited a time dependent increase in both water solubility and sorption.

Influence of Material and Surface Roughness of Resin Composite Cements on Fibroblast Behavior.

A well-polished cement surface increases the viability and spreading of gingival fibroblasts. The tested resin composite cements did not reveal any cytotoxic effects. Objective: This in vitro study aimed to investigate the effect of cement type and roughness on the viability and cell morphology of human gingival fibroblasts (HGF-1).Methods and Materials: Discs of three adhesive (Panavia V5 [PV5], Multilink Automix [MLA], RelyX Ultimate [RUL] and three self-adhesive (Panavia SA plus [PSA], SpeedCem plus [SCP], RelyX Unicem [RUN]) resin composite cements were prepared with three different roughnesses using silica paper grit P180, P400, or P2500. The cement specimens were characterized by surface roughness and energy-dispersive X-ray spectroscopic mapping. A viability assay was performed after 24 hours of incubation of HGF-1 cells on cement specimens. Cell morphology was examined with scanning electron microscopy.Results: The roughness of the specimens did not differ significantly among the different resin composite cements. Mean Ra values for the three surface treatments were 1.62 ± 0.34 μm for P180, 0.79 ± 0.20 μm for P400, and 0.17 ± 0.08 μm for P2500. HGF-1 viability was significantly influenced by the cement material and the specimens' roughness, with the highest viability for PSA ≥ RUN = MLA ≥ SCP = PV5 > RUL (p<0.05) and for P2500 = P400 > P180 (p<0.001). Cell morphology did not vary among the materials but was affected by the surface roughness.Conclusion: The composition of resin composite cements significantly affects the cell viability of HGF-1. Smooth resin composite cement surfaces with an Ra of 0.2-0.8 μm accelerate flat cell spreading and formation of filopodia.

Five-year Survival Rate of Bonded Dental Restorations in Frail Older Adults

Frail older adults residing in long-term care (LTC) facilities are among the most vulnerable to dental caries due to poor oral hygiene (OH), medication-related salivary hypofunction, carbohydrate-rich diets, and limited access to dental care. Providing dental restorations for LTC patients is challenging, and there are few studies investigating the longevity of restorations in this cohort. Multiple restorative materials have been used to restore tooth anatomy as well as address caries prevention using fluoride-based materials. This study examined the longevity of bonded direct restorations placed in LTC patients. Specifically, we examined whether a difference in survival exists between resin composite (RC) and glass ionomer cement (GIC) direct restorations in frail older adults residing in LTC. Tooth-colored restorations placed in LTC patients between 2007 and 2012, within the University of British Columbia Geriatric Dentistry Program, were followed annually up to 5 y or until they incurred an event (i.e., re-restoration or tooth extraction) or the patient was lost to follow-up or deceased. Restoration status was documented within the Clinical Oral Disorder in Elders (CODE) Index annual oral health assessments. Mixed-effect logistic regression was calculated to determine hazard ratios, address within-patient correlation, and measure the effect size of multiple covariates. A total of 3,201 dental restorations placed in 846 LTC patients were followed. This cohort of patients had a mean age of 86 y and high levels of oral and systemic disease. Over half were wheelchair bound and had compromised ability to perform OH. The overall 5-y survival rate was 60.3%, and there was no statistically significant difference in survival between RC and GIC. Tooth-colored restorations had reasonable longevity in LTC patients and had comparable survival to restorations placed in functionally independent, community-dwelling geriatric populations. No difference between RC and GIC was found with regards to restoration longevity in this population. Direct restorations provided to frail older adults residing in LTC have reasonable longevity and should be expected to survive for the remainder of the patient's life. As no detectable difference exists in survival rates between RC and GIC, operators should select appropriate restorative materials based on clinical conditions, patient factors, physical properties, and personal preference.

Forensic study of mechanical properties of dental restoration after burial in mangrove environment

Conducting research in the field of forensic sciences with methodologies that simulate situations found in the day-to-day practice of a given field of expertise is relevant insofar as this approach can produce results that are as close as possible to reality. In this context, the present study provided situations based on burial in a mangrove environment to estimate the changes in the mechanical properties (Knoop microhardness, roughness and color) of dental restorations utilizing silver amalgam, composite resin and glass ionomer cement over the time of burial. The silver amalgam showed a significant increase in surface roughness and a reduction in Knoop microhardness. Composite resin showed a statistically significant increase in color variation, and the glass ionomer cement showed significant increases in color variation and Knoop microhardness. These results allowed us to conclude that teeth restored with silver amalgam, composite resin and glass ionomer cement submitted to burial in mangrove environments produce different changes in surface roughness, Knoop microhardness and color properties depending on the time of burial to which the victims were submitted. These proprieties could help the forensic sciences to estimate time intervals for burial in mangrove environments.

Reattachment of a Dehydrated Tooth Fragment Using Retentive Screws

Coronal fracture of the anterior teeth is mainly common among children and adolescents. Though diverse treatment modalities are available, tooth fragment reattachment is generally considered a viable treatment option due to simplicity, natural aesthetics, and functional success. This paper presents a case of a 10.5-year-old female patient with a fractured maxillary central incisor with a dehydrated fragment. The dehydrated fragmented part was reattached with the help of retentive holes using an adhesive bonding agent and a resin composite cement. Follow-up at 15 months showed that the tooth was vital and functional with natural aesthetics.

Effect of grain size of dental zirconia on shear bond strength of composite resin cement.

The effect of grain size of dental zirconia on the shear bond strength of composite resin cement was newly studied. Disc-shaped dental zirconia with small (sample S) and large (sample L) grains were made by sintering of pre-sintered dental zirconia at 1450°C for 0.5 h and 40 h, respectively. After the sintering, the average grain size of sample S was 1.37 ± 0.15 µm, while that of sample L was 3.74 ± 0.50 µm. The sintered discs were successively polished with different grades of diamond and alumina slurries. The interfacial free energies were 63.5 ± 4.2 dyne/cm for sample S and 52.1 ± 5.5 dyne/cm for sample L. Stainless steel cylinders, previously sandblasted with 50 µm alumina powder, were bonded to the zirconia discs using composite resin cement. Next, samples were kept in an oven for 7 d at 36.5°C. The shear bond strength of sample S was 23.0 ± 4.5 MPa while that of sample L was 17.5 ± 4.6 MPa. After the fracture, the areal % values of composite resin cement remaining on the zirconia surfaces were 89.7 ± 5.9% for sample S and 61.6 ± 5.5% for sample L. The results suggest that grain size reduction has a potential to enhance the degree of bonding between a composite resin cement and a dental zirconia due to the increase of interfacial free energy.

Study and Shutoff Experiment on Mechanical Properties of Multistage Resin Composite Ductile Cement

In view of the traditional inorganic cement-based material hydration shrinkage caused by the impact of performance defects range of application, applying the principle of doping dispersion and compact packing, a multistage resin composite ductile cement slurry system with different temperatures was constructed. The compatibility, thickening and mechanical evaluation tests were carried out to optimize the resin type, doping amount and method. The results show that the thickening of the composite system is controllable, and the addition of resin is beneficial to improve the elastic deformation, whereas easy to pile up if adding extra amounts, and the compressive strength reduced. At the same time, adding resin first is beneficial to disperse in the cement gap. Compared with cement-based materials, the compressive strength increased 7% to 13%, the elastic modulus decreased 10% to 15%, and the deformation capacity increased 14% to 22%. Field test shows that it has good sealing performance and remarkable effect of oil increasing and dewatering, which provides a new technical means for controlling casing leakage and ensuring its normal production.

Effects of different toothpastes on the prevention of erosion in composite resin and glass ionomer cement enamel and dentin restorations.

Objective This study aimed to evaluate the effects of different toothpastes on the surface wear of enamel, dentin, composite resin (CR), and resin-modified glass ionomer cement (RMGIC), and to perform a topographic analysis of the surfaces, based on representative images generated by atomic force microscopy (AFM) after erosion-abrasion cycles.Methodology One hundred and forty bovine incisors were collected and divided into two groups: 72 enamel and 72 dentin blocks (4×4 mm). Half of the specimens were restored with CR (Filtek Z350 XT) and the other half with RMGIC (Fuji II LC). Then, samples were submitted to a demineralization cycle (5 days, 4×2 min/day, 1% citric acid, pH 3.2) and exposed to three different toothpastes (2×15 s/day): without fluoride (WF, n=12), sodium fluoride-based (NaF, n=12), and stannous fluoride-based (SnF2, n=12). Surface wear, as well as restoration interfaces wear, were investigated by profilometry of the dental substrates and restorative materials. All representative surfaces underwent AFM analysis. Data were analyzed by two-way analysis of variance and Tukey’s tests (α=0.05).Results NaF-based toothpaste caused the greater dentin surface wear (p<0.05). Toothpastes affected only enamel-restoration interfaces. AFM analysis showed precipitate formation in dentinal tubules caused by the use of fluoride toothpastes.Conclusions NaF-based toothpastes had no protective effect on enamel adjacent to CR and RMGIC against erosion-abrasion challenges, nor on dentin adjacent to RMGIC material. SnF2-based toothpastes caused more damage to interfaces between enamel and RMGIC.

Evaluation of the shear bond strength of resin cement to enamel after bleaching with Er: YAG and diode laser

Objective: The shear bond strength (SBS) of composite resin cement and color change to enamel bleached with two different concentrations of hydrogen peroxide (HP) bleaching agents in combination with two different laser applications was evaluated. Materials and Methods: The Er: YAG laser ( λ = 2940 nm) and diode laser ( λ = 940 nm) were used with the bleaching agent consisting of 40% HP opalescence (Opalescence Xtra Boost, Ulgen, South Jordan, UT, USA) and 35% HP whiteness (Whiteness HP Blue, FGM Dental Products, Joinville, SC, Brazil). Seventy-two human extracted teeth were randomly divided into two groups: For the 40% HP treatment, 36 specimens were divided into three subgroups: (1) HP agent with no laser treatment, (2) HP agent treated with Er: YAG laser, and (3) HP agent treated with diode laser. The same protocol was performed for the 35% HP. The color change was analyzed using the Commission Internationale de l’ Eclairage (CIE) L* a* b* system and surface roughness was analyzed by an atomic force microscope. The specimens were bonded with resin cement and a shear bond test was performed at 0.5 mm/min. The failure surfaces were evaluated using scanning electron microscope analysis. Results: Δ E value of the 40% HP + Er: YAG group was significantly higher than the other groups while diode groups showed the lower SBS values than the control groups ( p &lt; 0.05). Conclusions: The Er: YAG laser with 40% HP may be effective for the brighter teeth and the use of Er: YAG laser produced higher adhesion between enamel and resin cement than diode laser.

Color stability of computer aided design and computer aided manufacture composite ceramic/resin cements after accelerated ageing

Objective: To investigate the color stability of computer aided design and computer aided manufacture (CAD/CAM) composite ceramic/resin cements after accelerated ageing. Methods: Twelve groups (ten samples each group) were used as experimental groups, which were composed of CAD/CAM composite ceramic of three kinds of thickness (0.50, 0.75, 1.00 mm) (Lava Ultimate) associated with resin cements (Variolink N) of four colors (A1, A3, T, BL1). Another three groups of CAD/CAM composite ceramic/resin cements of three different kinds of thickness (0.50, 0.75, 1.00 mm) were used as control groups (ten samples each group). All samples were put into the xenon lamp ageing instrument to implement accelerated ageing. Spectrophotometers were used to measure the lightness (L(*)), red green color value (a(*)) and blue yellow color value (b(*)) of all samples before and after accelerated ageing process, and the changes of color variation (ΔE) was calculated. The effect of composite ceramic thickness and resin cement color on the changes of color variation (ΔE) before and after the ageing of CAD/CAM composite ceramic/resin cement and whether there was an interaction between them were tested by two-way ANOVA. Results: Before and after accelerated ageing, the ΔE of CAD/CAM composite ceramic/resin cements were <3.3. Two-way ANOVA showed that the thickness of CAD/CAM composite ceramics had an effect on ΔE (F=27.025, P<0.001), and the color of resin cement also had an effect on ΔE (F=15.606, P<0.001), but there was no interaction between them (F=0.534, P=0.829). Conclusions: The thickness of CAD/CAM composite ceramics and the color of resin cements could both affect the color stability of composite ceramic/resin cements combination. However, the resulted color change is within the clinically acceptable range.

Influence of Different Cleaning Procedures on Tensile Bond Strength Between Zirconia Abutment and Titanium Base.

To investigate the tensile bond strength between zirconia abutments and titanium bases, luted with two different resin composite cements, after different cleaning procedures. Zirconia abutments and titanium bases were luted with either a DMA/HEMA-based cement (n = 80; Multilink Hybrid Abutment, Ivoclar Vivadent) or a Bis-GMA/TEGDMA-based cement (n = 80; Panavia V5, Kuraray Noritake). The adhesive gap of half of the specimens was polished (n = 40 per resin composite cement). Four separate specimens underwent roughness measurements and scanning electron microscopy. The specimens were divided into four groups (n = 10 per subgroup): (1) not cleaned, (2) cleaning in an ultrasonic bath, (3) cleaning in an autoclave, and (4) treatment with low-pressure plasma. The specimens were thermocycled (20,000×, 5°C/55°C), tensile bond strength was tested, and fracture types were analyzed. Data were examined using the Kolmogorov-Smirnov test, univariate ANOVA with additional partial eta-squared (ηp2), and the Mann-Whitney U test. The defined level of significance was adjusted by Bonferroni correction (P < .003). The tensile bond strength of specimens luted with the DMA/HEMA-based cement was higher than that of specimens luted with the Bis-GMA/TEGDMA-based cement. The polishing step and the cleaning procedures showed no impact on tensile bond strength results. Specimens luted with the DMA/HEMA-based cement presented more cohesive fractures, whereas specimens luted with the Bis-GMA/TEGDMA-based cement presented themselves with more fractures of the interface between the resin composite cement and zirconia abutment. Ra values showed a decline in roughness after polishing for both resin composite cements. As the DMA/HEMA-based cement showed higher tensile bond strength values, the usage of this resin composite cement for luting implant abutments to titanium bases can be recommended. Neither polishing nor the use of different cleaning procedures had an impact on tensile bond strength.

Retrieval of Glass Fiber Post Using Er:YAG Laser and Conventional Endodontic Ultrasonic Method: An In Vitro Study.

To compare the times and temperatures used to remove a glass fiber post from an endodontically treated tooth using erbium-doped yttrium aluminum garnet (Er:YAG) compared to conventional endodontic ultrasonic method. Thirty-four single-root human extracted teeth were endodontically treated ex vivo. The post space was prepared to 7 mm in depth and a 11.4 mm glass fiber post was cemented using composite resin cement. Specimens were kept in 100% humidity for 24 hours and then randomly assigned to Er:YAG laser or ultrasonic methods for post removal. The removal time was recorded. Specimens with a fractured post during the removal process were excluded. The temperature on the external surface of the root was measured at the coronal, middle, and apical third portions during the laser or ultrasonic applications from 1 to 10 minutes. Data were analyzed using one-tailed t-test and paired t-test (ɑ = 0.01) for the post removal time and temperature difference, respectively. The specimen surfaces were examined using scanning electron microscopy (SEM). Fifteen specimens were tested in each group. Four specimens were fractured, 2 in the laser and 1 in ultrasonic group. One post was excluded because of laser tip damage. The average removal time were 98 ± 46.1 seconds for Er:YAG laser and 538 ± 215.6 seconds or ultrasonic groups with significant difference between the groups (p < 0.001). The temperature (°C) ranges measured from 1 to 10 minutes were [24.2°, 27.3°] for laser and [33.0°, 38.0°] for ultrasonic in the cervical area, [22.1°,24.6°] for laser and [31.0°, 34.6°] for ultrasonic in the middle area, and [24.4°, 27.7°] for laser and [30.3°, 34.1°] for ultrasonic in the apical area. There were significant differences between temperatures for each treatment (p < 0.001). SEM examination showed no visible damage caused by treatment with Er:YAG laser. Er:YAG laser can remove posts up to 5 times faster than ultrasonic removal method. The laser causes lower temperature increase at the root surface compared to the ultrasonic removal. Er:YAG may be considered as a viable alternative to sonication for post removal.